SU815477A1 - Displacement-to-analog signal converter - Google Patents

Description

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The invention is intended to convert linear and circular movements into a proportional voltage and can be used in automation systems for measuring linear movements of working bodies moving in hermetic volumes in the oil, mining and energy industries.

A discrete level gauge is known that contains a permanent magnet, a diode array, and a reed switch, each of which is enclosed by an excitation winding made in the form of counter-connected semi-windings, two. power supply and isolating diodes ij.

However, the complexity of the measurement circuit, due to the presence of a diode array and field windings located on each of the reed switches, reduces the reliability of the device and causes a low measurement accuracy.

A rotation angle sensor is known, which contains magnetic contacts divided into a precise reference system and a rough reference system, and a voltage divider connected to the corresponding magnetic controlled contacts t.2.

The disadvantage of this device is the need for two measuring devices.

Closest to the proposed

technically, there is a discrete level gauge containing a number of small and high-order reed switches located in a controlled range at a distance from each other. Reed switches of the same name younger. and each high-order bits are combined into parallel groups and divided into two independent channels. Reed switches shunt appropriate

5 of them are series-connected resistors. The effect of the reed switch is a permanent magnet. Information from the younger and older bits goes to two independent switch devices 3.

A disadvantage of the known device is the possibility of measuring movement error when moving an acting element (magnet) from one

S groups of reed switches to another group. For example, when moving upward, when only the last reed switch of the first group of the last bit is closed, one of the dial gauges is indi0. It quotes the last counting point of the youngest bit, and the other device has zero movement in the higher bit. . With further upward movement (forward), the devices should synchronously change information, i.e. the low-order device should indicate zero movement, and the high-level device should indicate the first reference point. When the magnet moves down (back, when moving from one group of reed switches to another, the indicating device also indicates an error: when the first reed switch is closed, the first reed switch of the previous upper discharge group closes, and the device induces the first reference point of the least significant discharge mark the older group, whereas the device must indicate only the corresponding point of the higher category. In addition, the presence of two devices makes it inconvenient to read the information. Enhancement of accuracy of conversion. The goal is achieved by converting linear and angular movements into an analog signal containing magnetically controlled junior and senior bits located at a certain distance from each other's DT and grouped in groups according to the number of measurement subranges, resistors. forming the high-voltage divider and high-low voltage divider, a permanent magnet placed on the object being monitored, a measuring device and a power source, into it A control key is introduced; one output of the magnetically controlled contacts of the lower bits, except the last one in the group, is connected via a control key and the positive power supply bus; another output of the magnetic control contacts of the lower bits, except the last one in the group, is connected to the corresponding point low-voltage divider, some terminals of the magnetic-controlled contacts of the secondary discharge are interconnected and connected to the negative bus of the power supply, other conclusions of the magnetic-controlled contacts of the old discharge in each oh -group is interconnected, connected to the corresponding point of the high-voltage divider, and to one of the conclusions of the last user-controlled contact of the lower-order bits of the corresponding group, and the second conclusions of the last magnetocontrol of conacts in each group of the younger bits are combined between each other and connected to the control output of the controllable key, the voltage dividers of the low-order and high-order bits are connected to each other, and the common point is connected to the bus of zero potential of the power supply, one output is measured Device ceiling elements connected to one of the voltage divider resistors Tarsch discharge, and the other terminal of one of the voltage divider resistors least significant bit. Fig. 1 shows a circuit diagram of a displacement transducer into an analog signal} in Fig. 2 — a characteristic of the output voltage of the transducer. Consider the operation of the transducer on the example of a linear displacement transducer into an analog signal. The converter contains a power source 1, a control switch 2, three groups of magnetically controlled contacts (reed switches) 3-5 junior bits, two groups of magnetically controlled contacts (reed switches) b and 7 higher bits, resistors 8-11, forming a voltage divider connected to the reed channel of the low-order channel, resistors 12 and 13, forming the voltage divider of the high-reed channel of the reed switch, showing the device 14 and the permanent magnet 15 associated with the controlled organ. The controllable organ and the non-magnetic tube on which the reed switches and resistors are located are not shown in the diagram. Each group of low and high bits contains 5 reed switches, in principle, the number of reed switches in a group can be increased or decreased depending on the resolution of the conversion. With the received number of groups and Chiselecons in the group, the converter allows to measure linear movement of the controlled organ (magnet in the range of 280 mm with a resolution of 20 mm. The resistance values of the resistors 8-11 are chosen such that when the power supply voltage is 10 V the closure of any reed switch in the low-order groups increases the voltage shown by the device 14 by 0.2 V, and the closure of any reed switch from the high-end groups increases the voltage shown by the device 14 by 1 V. The device works as follows: When the controlled body reaches (the magnet 15 is in position corresponding to the closure of the reed switch 3. youngest bit, the latter closes. A circuit passes through the circuit of elements 1 - 2 - 3 - 8 - 9 - 10 - 14 - 12 - 1, indicating device 14 shows 0.2 V, i.e., the first reference point or 20 mm of movement of the monitored organ. Next, the monitored organ with magnet 15 reaches the reed switch 3 (the reed switch 3 has not opened yet), which is closed, and

the current in the measuring circuit is increased due to the removal from the current circuit of the resistor 8, the device 14 shows the next reference point, i.e. voltage 0.4 V or forward movement () of the controllable organ by 40 mm. When a reed switch is closed with a magnet Zd, the device 14 shows a 0.8 V or 80 mm displacement. During further movement of the magnet, the reed switch is closed, but the readings of the device 14 do not change, since it is not connected with the low-voltage divider. When the reed switch 6 is turned on, the locking element 2 is turned on and the low-order reed switches from the current source.1 are disconnected, and the current circuit is closed through the elements 6, 13, -14, 11 and 1. At the same time, the device 14 induces a voltage of 1B corresponding to 100 mm displacement. In this way, an error in conversion during the transition of a magnet from one group of reed switches to another is eliminated.

Upon further movement of the controllable organ with the magnet 15 up (forward), the reed switch ZD opens, but the reed switches remain closed and 6 and the control key 2 is in the on state and blocks the power of the low-order reed switches, therefore the information does not change. When the reed switch 3 is opened and the magnet 15 moves up (forward) the reed switch 4 of the second group of the younger one is discharged closed, the control key 2 is de-energized and the reed switches of its low voltage are again connected to the power source 1. The device 14 indicates that the controlled organ is moving up (forward) 120 mm, i.e. the voltage on the device is equal to the sum of the voltages from the two dividers of the voltage divider formed by resistors 8-11, and the divider formed by resistors 12 and 13. Further movement of the monitored organ with the magnet 15. forward causes the reed switch 42 to close yes it increases by 0.2V, and the device 14 shows 140m displacement, since all the reed switches

 connected to the same

At the same point, the divider voltage of the senior bit. Similarly, the device operates on the entire range of movement of the controlled body forward (upward

When the controlled organ with the magnet 15 is moving down (back), the reed switch 42 opens, and the device 14 shows again 120 mm displacement. Subsequently, the reed switches 6 and 3 are closed, the blocking element 2 turns on and disconnects the low-end reed switches from the power source, and the device shows 100 mm displacements. After the reed switch closes 3. and the reed switch 6 is opened, the control key

2 Is de-energized, and the low-order reed switches are again connected to the power source 1, the device 14 shows 80 mm displacements. The device works in a similar way on the whole range of movement of the controlled organ.

Control key 2 can be you. 1), and can be performed on a single transistor, which closes when closed

Q of the first reed switch in each group of the highest discharge and the last in each group of reed switches of the younger discharge. Thus, the introduction of a block element into the device allows 5 to eliminate the conversion error, i.e. to increase the accuracy, and the presentation of information of the junior and senior bits on a single indicating instrument creates greater convenience in reading the scientific research institute of information and eliminates the possibility of an error in reading.

In addition, the converted motion signal from one device is conveniently transmitted to an automated system for controlling the operation of the installation, which is not possible with the known device.

Claims (3)

Invention Formula Q Displacement transducer to analog signal containing magnetically controlled contacts of the lower and higher digits located at a certain distance from each other  and combined into groups according to the number of measurement subranges, resistors, the formation of a high voltage divider and a low voltage voltage divider, a permanent magnet on the monitored object, a measuring device and a power source, characterized in that, in order to improve the accuracy of conversion, A managed key is entered into it. one pin magnetic contacts 5 low-order bits, except the last one in the group, are connected via a controllable positive power supply bus, another output of the magnetically controlled contacts of the lower-order bits, besides the latter in the group, is connected to the corresponding point of the low-voltage divider, only the outputs of the magnetically controlled the high-order contacts are interconnected and connected to the minus bus of the source, 1 tani, the other conclusions of the magnetically controlled high-voltage contacts in each group are interconnected, connected to the corresponding point d voltage divisor MSB fi and the one of the terminals of the last magnitoupravl emogo -CONTACT low bits of the corresponding group, and the latter, recent findings magnitoupravl proxy contacts in each group The 5 low-order bits are interconnected and connected to the control output of the controlled key, the voltage dividers of the low-order and high-order bits are connected to each other, and a common point is connected to the power supply potential zero bus, one output of the measuring device is connected to one of the resistors the high-voltage divider and the other conclusion to one of the resistors of the low-voltage divider. Sources of information that are considered in the examination 1. USSR author's certificate 434271, cl. G 01 F 23/12, 1972, 2. USSR author's certificate 399897, class G 01 C 9/04, 1973. 3. USSR author's certificate 556337, cl. G 01 F 23/12, 1975 rototype).